Patients that suffer from diabetic neuropathy gradually lose sensing function in their lower extremities, particularly their feet. Yet neuropathic patients can maintain motor function, such that they can continue walking on, e.g., applying pressure and exposing to possible injury, feet for which they may have lost nociception. Nociception is the sensory or neural capacity to recognize adverse or noxious stimuli. With loss of nociception, patients can have an increased risk of developing a serious injury or ulcer on their feet; when a patient does not feel a pressure point or wound as painful or uncomfortable, he or she may not notice an issue before it has progressed to a serious, highly noticeable degree. For example, Diabetic Foot Ulcers (DFU's) may sometimes only be recognized when blood begins to appear on a patient's sock, a point at which ischemia, e.g., tissue death, which started at an internal tissue region has already progressed through tissue to an outer layer, and amputation may be necessary. 15% to 25% of diabetic patients are likely to develop a DFU in their lifetimes. DFU's can lead to hospitalization, amputation, and ultimately a heightened patient morbidity risk.
Regular inspection and analysis of a diabetic patient's feet can help lower the risk of DFU formation and may have other benefits for improving the health of the patient's feet. However, it can be physically difficult for a diabetic patient to view his or her feet, and further difficult for a patient to discern from a cursory view indications of a developing wound. Foot imaging devices have been introduced for shoe-fitting applications, such as determining the appropriate size or insole for an athletic or walking shoe, or advanced clinical use, such as hyperspectral imaging applications. A limited number of devices have been proposed for patient viewing of his or her feet outside of a clinic. However, none of the existing devices provide sufficient information for analysis of the health of a patient's foot or a structure that is suitable for in-home use.
What is needed is a device suitable for in-home use and providing sufficient monitoring of the health of a patient's feet, particularly to avoid the development of diabetic foot ulcers.